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Heat Pipes
Published in Juan Cepeda-Rizo, Jeremiah Gayle, Joshua Ravich, Thermal and Structural Electronic Packaging Analysis for Space and Extreme Environments, 2021
Juan Cepeda-Rizo, Jeremiah Gayle, Joshua Ravich
After the thermal switching cryogenic heat pipe was manufactured and assembled in accordance with the Figure 7.3 design at the ATK manufacturing facility in Beltsville, MD, the unit was then configured for thermal vacuum testing. Figure 7.4 illustrates the overall test setup, thermocouple locations, heater placement, and MLI coverage (note: heater labels are preceded by the letter “H” and MLI is depicted by the dotted red lines). The unit was mounted in ATK Chamber E, which has a full 360° LN2-cooled, box-shaped shroud. Figure 7.5 illustrates the thermal vacuum chamber used at the ATK test facilities in Beltsville, MD. After the placement of the thermal switching cryogenic heat pipe assembly on the flat interior bottom surface of the shroud, a transit and ruler were used to level the unit so that it would have a slightly adverse tilt. The arbitrary tilt specification specified in the test plan required that the evaporator would be 1.3 +/− 0.5 mm above the condenser.
Optical Instrument Structural Design
Published in Paul Yoder, Daniel Vukobratovich, Opto-Mechanical Systems Design, 2017
In their 1989 paper, Zurmehly and Hookman also described a test facility used to test the effects of simulated temperature changes in focus, pointing, and pointing error repeatability. Figure 7.53 shows a portion of the facility. The test item was mounted rigidly inside a thermal vacuum chamber (dotted line) on a vibration isolation table. A back-illuminated pinhole light source was placed at the focal point of the GOES telescope (at right in the figure). The collimated beam from the telescope passed through a window in the chamber wall into a modified commercial (14 in. aperture Celestron) telescope where it was focused through a beam splitter cube to the focal point of the latter telescope. The image was viewed through a microscope (not shown). The microscope was mounted on a three- axis adjustable stage equipped with means for measurement of all three motions. When the focus of the GOES telescope varied or the image wandered laterally because of temperature changes, the microscope was used to measure those shifts. From the known longitudinal and lateral magnifications of the combination of telescopes, the corresponding errors for the test item were calculated.
Vibration Testing and Finite Element Analysis of Inflatable Structures
Published in Norman M. Wereley, Inderjit Chopra, Darryll J. Pines, Twelfth International Conference on Adaptive Structures and Technologies, 2017
Marion Sausse, Eric Ruggiero, Gyuhae Park, Daniel J. Inman, John A. Main
Griffith and Main [4] used a modified impact hammer to excite the global modes of the structure while avoiding local excitation. Lassiter et al. [5] tested a torus attached to three struts with a lens in a thermal vacuum chamber. They found significant differences in the response between the structure in ambient and vacuum conditions. Park et al. [6] investigated the feasibility of using smart materials, such as PVDF films, to find modal parameters and to attenuate vibration in a flexible inflated structure.
Hybridization of TRIZ and CAD-analysis at the conceptual design stage.
Published in International Journal of Computer Integrated Manufacturing, 2019
Shazmira Azwa Sauli, Mohamad Ridzwan Ishak, Faizal Mustapha, Noorfaizal Yidris, Sanusi Hamat
This design inspired by the cross element of a jack system, and it also known as the scissor system. This device is to transfer a unit testing of the satellite body into the thermal vacuum chamber (TVC). The loader consisting of three (3) modules, there is a base module (Module 1), Scissor Module (Module 2) and Deck module (Module 3). The case study will focus on Module 2. Refers to Figure 5, the illustration shows the full assembly of the scissor module. The scissor structure uses to lift (up and down) the upper platform (module 3. The goal is to improve the development of this current design and to reduce the weight of the assembly. The structure must be enduring high load applied on the top platform (module 3) and withstand the load from the top platform itself.
Development of Engineering Qualification Model of a Small ETG for a Launch Environmental Test
Published in Nuclear Technology, 2021
Jintae Hong, Kwang-Jae Son, Jong-Bum Kim, Jin-Joo Kim
A thermal vacuum test was also performed to test the temperature change in a space environment using the small ETG, which was subjected to a heat cycle test. The test was conducted in KTL’s thermal vacuum chamber (TVC1.0) for 2.5 cycles (Fig. 15). The chamber was evacuated to less than 1.0E-5 Pa, and the experimental temperature range was between −70°C and 60°C. Figure 16 shows the performance test results after the thermal vacuum test, and all sensors and the thermoelectric module show normal operation. Because the function test was performed in the thermal vacuum chamber before the small ETG stabilized, the function graph in Fig. 16 shows more severe perturbation than the previous function graphs of Figs. 10 and Figs. 12.
Application of high-thermal-conductivity diamond for space phased array antenna
Published in Functional Diamond, 2022
Wei Lu, Jin Li, Jianyin Miao, Liangxian Chen, Junjun Wei, Jinlong Liu, Chengming Li
Figure 4 shows a photograph of the whole antenna in the vacuum chamber during the thermal balance test. The whole-system-level thermal balance test of the antenna was carried out in a thermal vacuum chamber. The test results showed that the temperature level of all T/R modules was in the range of 15.3–19.3 °C, with a maximum temperature gradient of 1.9 °C. Ground tests verified the efficient heat collection and transfer from multiple distributed point heat sources of the T/R modules. The thermal matching design of the diamond and the metal frame proved to be valid with the T/R module temperature gradient of 1.9 °C, showing an outstanding heat dissipation performance. Figure 5 shows a thermal analysis temperature mapping based on thermal results.